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// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// cgo was incorrectly adding padding after a packed struct.
package cgotest
/*
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
typedef struct {
void *f1;
uint32_t f2;
} __attribute__((__packed__)) innerPacked;
typedef struct {
innerPacked g1;
uint64_t g2;
} outerPacked;
typedef struct {
void *f1;
uint32_t f2;
} innerUnpacked;
typedef struct {
innerUnpacked g1;
uint64_t g2;
} outerUnpacked;
size_t offset(int x) {
switch (x) {
case 0:
return offsetof(innerPacked, f2);
case 1:
return offsetof(outerPacked, g2);
case 2:
return offsetof(innerUnpacked, f2);
case 3:
return offsetof(outerUnpacked, g2);
default:
abort();
}
}
*/
import "C"
import (
"testing"
"unsafe"
)
func offset(i int) uintptr {
var pi C.innerPacked
var po C.outerPacked
var ui C.innerUnpacked
var uo C.outerUnpacked
switch i {
case 0:
return unsafe.Offsetof(pi.f2)
case 1:
return unsafe.Offsetof(po.g2)
case 2:
return unsafe.Offsetof(ui.f2)
case 3:
return unsafe.Offsetof(uo.g2)
default:
panic("can't happen")
}
}
func test28896(t *testing.T) {
for i := 0; i < 4; i++ {
c := uintptr(C.offset(C.int(i)))
g := offset(i)
if c != g {
t.Errorf("%d: C: %d != Go %d", i, c, g)
}
}
}
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